McCain is set to hit the air in 20 Super Tuesday states with an ad called True Conservative.

(CNN) - John McCain is poised to purchase a "significant" Super Tuesday ad buy that will put the Arizona senator's television commercials on the air in some 20 states, campaign sources tell CNN.

The ads are set to hit airwaves in every Super Tuesday state except Utah.

The sources refused to give a specific dollar figure, but said it was a "seven figure" buy.

McCain, whose campaign of late has seen an infusion of cash, spent close to $2 million on ads in Florida alone the week before that state's crucial primary.

The news comes the same day Mitt Romney's campaign announced it was making a significant ad buy in California and some other Super Tuesday states.

UPDATE: McCain's campaign has released details of the ad it's set to run. Called "true conservative," it touts the Arizona senator's "commitment to conservative principles on economic, social and national security issues as well as his readiness to lead as commander in chief on day one. "